Variable height central bearing



7, 1968 J. J. REECE ETAL 3,399,006

VARIABLE HEIGHT CENTRAL BEARING Filed Sept. 6. 1966 l i ---4 r--" I -fiFIG-2 INVENTORS JAMES J. REECE THOMAS C BARTON ATTORNEY Patented Aug.27, 1968 3,399,006 VARIABLE HEIGHT CENTRAL BEARING James J. Reece,Caseyville, Ill., and Thomas C. Barton, Ardmore, PZL, assignors toGeneral Steel Industries, Inc., Granite City, Ill., a corporation ofDelaware Filed Sept. 6, 1966, Ser. No. 577,342 7 Claims. (Cl. 308-137)The invention relates to railway rolling stock and consists particularlyin an improved central bearing for pivotally supporting a railwayvehicle body on a truck.

After continued use, the diameter of car wheel treads is substantiallyreduced by wear and thus results in a proportional lowering of the carbody. This is particularly serious on cars used in train service wherecoupler height must be maintained substantially constant and uniform topermit coupling of cars in the trains, and on many commuter and rapidtransit lines where station platforms and normal car floor heights aresubstantially coplanar with each other to permit rapid loading andunloading of cars. Wheel wear can be corrected for by shirnming thesprings by which sprung structure is supported from unsprung structure,but this procedure is complicated by the fact that the springs at eachside must be equally shimmed, and in trucks provided with air springscontrolled by leveling valves shimming of the springs may requireadjustment of the valves and their control linkages. As a matter ofpractice it has been found that the most effective and simple way tocorrect for wheel wear is to shim the center plate or central bearing bywhich the car body is pivotally supported on truck structure. Withpresent methods of applying shims to central bearings of the typedisclosed in J. C. Travilla Patent 2,655,117, of which applicantsassignee is the owner by assignment, the top member of the bearing mustbe completely separated from the bottom member to permit the insertionof annular shims around the cylindrical depending central portion of thetop member, and because the shims must be prevented from rotatingrelative to each other and to the bottom horizontal surface of the topmember, they must be welded or otherwise secured to the bottom surfaceof the top member. Otherwise rotation will take place between theminstead of between metal surfaces and the friction material linerinterposed between the top and bottom horizontal members, thusnullifying the shimmy resisting effect of the friction member.

It is an object of the present invention to provide improved means forshimming central bearings without necessitating full separation of thesupporting and supported parts.

It is a further object to provide means for shimming central bearings ofthe type referred to above including means rendering unnecessarysecurement of the shims to one of the central bearing members to preventtheir rotation.

The foregoing and additional more detailed objects and advantages of theinvention will be evident from the following description and theaccompanying drawings, in which:

FIG. 1 is a transverse vertical sectional view of a railway vehicletruck embodying the invention.

FIG. 2 is an enlarged fragmentary view of the central portion of thetruck structure shown in FIG. 1, showing the central bearing.

FIG. 3 is a horizontal sectional view along line 33 of FIG. 2.

FIG. 4 is a horizontal sectional view of the central bearing annularplate, along line 4-4 of FIG. 2

The truck shown in FIG. 1 includes wheels 1, an axle 3, side frames 5supported from axle 3 laterally inwardly of wheels 1, and a framecomprising longitudinally ex tending box section side members 7supported on side frames 5 and connected to each other by a transversetransom structure 9. Transom 9 is of box section having spaced apartside walls 11, 11, substantially horizontal top walls 13, and bottomwall 15. At its center wall 13 is formed with a depression defined byvertical cylindrical wall 17 and a horizontal bottom wall 19. Radiallyoutwardly of depression 17, 19 the upper wall 13 is formed with anupwardly facing annular surface 21 on which is seated a correspondingannular pad 23 of brake lining material having a high coefficient offriction.

A transverse bolster 25, also of box section, i.e., having spaced sidewalls 27, 27, substantially horizontal top wall 29 and bottom wall 31,mounts spring groups S, S at its ends for supporting a car body. Bottomwall 31 is formed with a downwardly projecting vertical cylindrical wall33, of slightly less diameter than truck frame transom cylindrical wall17, for mating receipt therein, the annular space therebetween beingoccupied by an annular frictional sleeve 35, the latter being maintainedat proper height on wall 33 by an annular shoulder 37 along the lowermargin of the latter. Surrounding cylindrical wall 33 the bottom surface39 of bolster bottom wall 31 is fiat, and is formed with a plurality ofequiangularly spaced holes 41, preferably spaced apart and positioned onthe transverse and longitudinal center lines respectively of the truckand the bolster. Between bottom surface 39 of the bolster and frictionpad 23 is positioned an annular metal plate 43 in contact with the topsurface of pad 23. Plate 43 mounts a plurality of upstanding pins 45adapted to register with and extend through holes 41 in the bolsterbottom wall and thus maintain plate 43 against rotation relativethereto, the bolster bottom wall being adapted to rest directly on theupper surface of plate 43 as shown in broken lines on FIG. 2. With thisarrangement, vertical load is transmitted directly from bottom wall 31through plate 43 and friction pad 23 to top wall 13 of the truck frametransom, the frictional resistance between friction pad 23 and trucktransom top surface 21 and the bottom surface of plate 43 opposingtendencies of the truck to oscillate about its vertical axis relative tothe bolster. The interaction of pins 45 and holes 41 in the bolsterbottom wall prevent any relative rotation of plate 43 with respect tothe bottom surface of bolster bottom Wall whereby relative rotation ofthe bolster and truck portions of the hearing would be freelyaccommodated by the metal-to-metal engagement of the top wall plate 43and the bottom wall of the bolster instead of the higher frictionalcontact between bottom surface of plate 43 and the top surface offriction pad 23.

In order to raise the bolster with respect to the truck frame so as tocompensate for wheel wear, yet make it unnecessary to separate thebolster and truck frame completely at the central bearing, semiannularshims 47 are provided. Shims 47 are in the form of arcs slightly lessthan so that they can be inserted from either side, the space betweenthem providing clearance for a pair of diametrically opposite pins 45 onplate 43. At their midpoints shims 47 are formed with radial slotsextending outwardly from their inner margins a sufficient distance toclear the other pair of pins 45 on plate 43.

Operation of the device is as follows: When excessive wheel wear isnoted, the bolster may be jacked to a height sufiicient to provide theproper car floor and coupler height from the broken line position shownin FIG. 2, then the bolster is seated directly on plate 43. When thebolster is thus elevated, plate 43 remains by gravity seated on frictionpad 23 and thus spaced vertically from the bottom surface 39 of bolsterbottom wall 31. As many shims 47 as may be needed to elevate thebolster, and with it the car body to the desired height may then beinserted without separating the vertical cylindrical wall surfaces 33and 17. After insertion of the desired shims 47 the jack may be let downto lower bolster 25 and with it bottom wall 31 onto the surface of theshims. Since pins 45 are of sufficient length to accommodate anyanticipated number of shims, plate 43 will be maintained againstrotation irrespective of the number of shims inserted within thisanticipated limit, and undesired rotation of the bolster relative totruck frame transom 9 will be opposed by the frictional resistancebetween the bottom surface of plate 43 and friction pad 23, and betweenthe latter and top surface 21 of transom 9.

Details of the central bearing may be modified substantially withoutdeparting from the spirit of the invention and exclusive use of suchmodifications as come within the scope of the appended claims iscontemplated.

What is claimed is:

1. In a central bearing for railway vehicles, a top member, a bottommember, one of said members being formed with a cylindrical wall recessand the other of said members being formed with a cylindrical wallprojection pivotally received in said recess, opposing horizontalsurfaces on said members surrounding said projection and recess therein,an annular plate surrounding said recess and projection, and meansretaining said plate against rotation relative to one of said memberswhile accommodating substantial vertical movement between said plate andsaid one member whereby to permit the insertion therebetween of shims asdesired.

2. A central bearing according to claim 1 wherein said last named meanscomprises registering openings in the surface of one of said members ofsaid same member and cylindrical projections on said plate in registrywith said holes, said projections extending parallel to the axis of saidcylindrical walls.

3. A central bearing according to claim 2 wherein there is a pluralityof said cylindrical elements in registering holes.

4. A central bearing according to claim 3 including shims of annularsector shape of sufficient size to be disposed between adjacent pairs ofcylindrical members.

5. A central bearing according to claim 4 wherein there are additionalpins between said named pins and said shims are radially slotted toclear said additional pins.

6. A central bearing according to claim 5 wherein said first named pinsare diametrically opposed to each other and said last named pins are ona diameter at right angles to the first diameter, said shims beingsubstantially semiannular sectors.

7. A central bearing according to claim 1 in which there is a flatannular pad of friction material disposed between said annular plate andsaid other member.

References Cited UNITED STATES PATENTS 2,655,117 10/1953 Travilla 308l37MARTIN P. SCHWADRON, Primary Examiner.'

FRANK SUSKO, Assistant Examiner.

1. IN A CENTRAL BEARING FOR RAILWAY VEHICLES, A TOP MEMBER, A BOTTOMMEMBER, ONE OF SAID MEMBERS BEING FORMED WITH A CYLINDRICAL WALL RECESSAND THE OTHER OF SAID MEMBERS BEING FORMED WITH A CYLINDRICAL WALLPROJECTION PIVOTALLY RECEIVED IN SAID RECESS, OPPOSING HORIZONTALSURFACES ON SAID MEMBERS SURROUNDING SAID PROJECTION AND RECESS THEREIN,AN ANNULAR PLATE SURROUNDING SAID RECESS AND PROJECTION, AND MEANSRETAINING SAID PLATE AGAINST ROTATION RELATIVE TO ONE OF SAID MEMBERSWHILE ACCOMMODATING SUBSTANTIAL VERTICAL MOVEMENT BETWEEN SAID PLATE ANDSAID ONE MEMBER WHEREBY TO PERMIT THE INSERTION THEREBETWEEN OF SHIMS ASDESIRED.